Sy. Kim et al., EFFECT OF HEARTMATE LEFT-VENTRICULAR ASSIST DEVICE ON CARDIAC AUTONOMIC NERVOUS ACTIVITY, The Annals of thoracic surgery, 61(2), 1996, pp. 591-593
Background. Clinical performance of a left ventricular assist device i
s assessed via hemodynamic parameters and end-organ function. This stu
dy examined effect of a left ventricular assist device on human neurop
hysiology. Methods. This study evaluated the time course change of car
diac autonomic activity of 3 patients during support with a left ventr
icular assist device before cardiac transplantation. Cardiac autonomic
activity was determined by power spectral analysis of short-term hear
t rate variability. The heart rate variability before cardiac transpla
ntation tvas compared with that on the day before left ventricular ass
ist device implantation. Results. The standard deviation of the mean o
f the R-R intervals of the electrocardiogram, an index of vagal activi
ty, increased to 27 +/- 7 ms from 8 +/- 0.6 ms. The modulus of power s
pectral components increased. Low frequency (sympathetic activity) and
high frequency power (vagal activity) increased by a mean of 9 and 22
times of each baseline value (low frequency power, 5.2 +/- 3.0 ms(2);
high frequency power, 2.1 +/- 0.7 ms(2)). The low over high frequency
power ratio decreased substantially, indicating an improvement of car
diac sympatho-vagal balance. Conclusions. The study results suggest th
at left ventricular assist device support before cardiac transplantati
on may exert a favorable effect on cardiac autonomic control in patien
ts with severe heart failure.